You will get efficient and thoughtful service from Xindian Construction.
Note: All code references cited in this answer are from NFPA-70:2014 (the 2014 NEC).
Question #1: It looks like you have it right that the installation is in violation of 312.5(C). The code reference is attached at bottom of my answer.
Question #2: I could see an argument for installing NM cable outside of conduit so long as the cable originates from a punch-out toward the middle of the panel. The reason I say this is that you effectively have EMT providing protection against physical damage on all sides around it. That call would ultimately be up to the inspector's opinion though -- the same goes for all calls on "subject to physical damage" since the NEC doesn't define it.
Question #3: You will note that flexible conduit is not expressly allowed by 312.5(C) and expressly specifies only two allowable methods: securing the cable and specific uses of nonflexible raceways. Also, all flexible conduit options are subject to the same "cannot be used where subject to physical damage" restrictions as NM, so it wouldn't do any good in this case even if it were allowed since the NM cable is being protected because it is subject to physical damage.
Just to show the specific prohibitions on the various flexible conduit options:
ARTICLE 348 Flexible Metal Conduit: Type FMC
348.12 Uses Not Permitted. FMC shall not be used in the following:
(7) Where subject to physical damage
ARTICLE 350 Liquidtight Flexible Metal Conduit: Type LFMC
350.12 Uses Not Permitted. LFMC shall not be used as follows:
(1) Where subject to physical damage
ARTICLE 356 Liquidtight Flexible Nonmetallic Conduit: Type LFNC
356.12 Uses Not Permitted. LFNC shall not be used as follows:
(1) Where subject to physical damage
ARTICLE 360 Flexible Metallic Tubing: Type FMT
360.12 Uses Not Permitted. FMT shall not be used as follows:
(5) Where subject to physical damage
ARTICLE 362 Electrical Nonmetallic Tubing: Type ENT
362.12 Uses Not Permitted. ENT shall not be used in the following:
(9) Where subject to physical damage
ARTICLE 320 ARMORED CABLE: TYPE AC
320.12 Uses Not Permitted. Type AC cable shall not be used as follows:
(1) Where subject to physical damage
ARTICLE 330 METAL-CLAD CABLE: TYPE MC
330.12 Uses Not Permitted. Type MC cable shall not be used under either of the following conditions:
(1) Where subject to physical damage
I think that has it covered.
312.5 Cabinets, Cutout Boxes, and Meter Socket Enclosures. Conductors entering enclosures within the scope of this article shall be protected from abrasion and shall comply with 312.5(A) through (C).
(C) Cables. Where cable is used, each cable shall be secured to the cabinet, cutout box, or meter socket enclosure. Exception: Cables with entirely nonmetallic sheaths shall be permitted to enter the top of a surface-mounted enclosure through one or more nonflexible raceways not less than 450 mm (18 in.) and not more than 3.0 m (10 ft) in length, provided all of the following conditions are met:
(a) Each cable is fastened within 300 mm (12 in.), measured along the sheath, of the outer end of the raceway
(b) The raceway extends directly above the enclosure and does not penetrate a structural ceiling.
(c) A fitting is provided on each end of the raceway to protect the cable(s) from abrasion and the fittings remain accessible after installation.
(d) The raceway is sealed or plugged at the outer end using approved means so as to prevent access to the enclosure through the raceway.
(e) The cable sheath is continuous through the raceway and extends into the enclosure beyond the fitting not less than 6 mm (1⁄4 in.).
(f) The raceway is fastened at its outer end and at other points in accordance with the applicable article.
(g) Where installed as conduit or tubing, the cable fill does not exceed the amount that would be permitted for complete conduit or tubing systems by Table 1 of Chapter 9 of this Code and all applicable notes thereto. Informational Note: See Table 1 in Chapter 9, including Note 9, for allowable cable fill in circular raceways. See 310.15(B)(3)(a) for required ampacity reductions for multiple cables installed in a common raceway.
Are you ready to organize your wires and cables? You’ve purchased braided sleeving, but you may have one question that still looms: "How am I going to terminate the ends?"
Before we delve into how-to finish your sleeving, let’s start with a few braided sleeving cutting basics. It’s important to properly cut it because there are some types that fray with scissors — those types should be cut with a hot knife. There are some woven kinds that are designed to be fray-resistant — and those can be trimmed with scissors. You will also find some braided sleeving materials, like Kevlar®, cut best with special shears.
This how-to guide lets you in on the details and supplies needed for four easy braided sleeving finishing methods. Just read on!
Are you interested in learning more about Expandable Container House Manufacturers? Contact us today to secure an expert consultation!